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Intra- and Intermolecular Oxa-Pictet–Spengler Cyclization Strategy for the Enantioselective Synthesis of Deoxy Analogues of (+)-Nanomycin A Methyl Ester, (+)-Eleutherin, (+)-Allo-Eleutherin, and (+)-Thysanone

✍ Scribed by Rajiv T. Sawant; Satish G. Jadhav; Suresh B. Waghmode


Publisher
John Wiley and Sons
Year
2010
Tongue
English
Weight
229 KB
Volume
2010
Category
Article
ISSN
1434-193X

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✦ Synopsis


Abstract

Enantioselective synthesis of deoxy analogues of pyranonaphthoquinone antibiotics (+)‐nanomycin A methyl ester, (+)‐eleutherin, (+)‐allo‐eleutherin, and (+)‐thysanone was achieved in good overall yield with high enantio‐ and diastereoselectivity from the common intermediate (R)‐3‐(2,5‐dimethoxyphenyl)propane‐1,2‐diol. The intramolecular oxa‐Pictet–Spengler cyclization of 6‐aryl‐1,3‐dioxolone was developed for the first time and utilized in the enantioselective synthesis of (+)‐deoxynanomycin A methyl ester, whereas the intermolecular oxa‐Pictet–Spengler cyclization strategy was applied to the enantioselective synthesis of deoxy analogues of (+)‐eleutherin, (+)‐allo‐eleutherin, and (+)‐thysanone.